This invention pertains to the art of interconnecting a fluid system device to a main process line and more particularly to eliminating a separate tee fitting and associated secondary line extending between the tee fitting and fluid system device.
The invention is particularly applicable to modifying an end member of a known valve body arrangement and will be described with particular reference to a ball valve housing. However, it will be appreciated that the invention has broader applications and may be utilized with similar fluid system devices.
Commonly assigned U.S. Pat. No. 3,981,482 to Callahan, Jr., et al. issued Sept. 21, 1976 is directed to a ball valve structure that has met with substantial commercial success. For purposes of brevity, the disclosure of that patent is hereby incorporated by reference. According to the structural arrangement of that patent, a three part valve body includes first and second end members received on opposite ends of a central body portion. A plurality of elongated tie members or bolts extend through selected portions of the three part body. Through removal of a predetermined tie bolt, the central body portion swings away or pivots relative to the opposed end members which are maintained fixed relative to one another by the remaining tie bolts. The valve body is still disposed in-line during the swing away action so that complete removal from a fluid line and disassembly of the valve body are avoided. This arrangement facilitates ease of servicing valve seats received in the central body portion on opposite sides of a ball member.
Although the detailed description in the noted patent is directed to a ball valve the disclosure recognizes that the same body portions, end members, and tie bolt relationships can be employed in many different fluid system devices. By way of example, filters, flow gauges, check valves, pinch valves, and the like can advantageously be designed to use the inventive body or housing arrangement.
Flow system devices of this type generally include a passage through each end member that facilitates makeup with an associated fluid system through conventional pipe connection means. For example, and as illustrated in the referenced patent, standard pipe threads may be provided in the passages as one means to facilitate ease of assembly of the fluid systems. Passages through the end members are generally aligned along a longitudinal axis so that the flow system device may be disposed in-line. To accommodate an in-line device of this type, at least four regions along the flow path must be sealed to the external environment. Particularly, (i) the juncture between the fluid line and the inlet passage of one end member, (ii) the interface between the inlet end member and the central valve body portion, (iii) the interface between the central valve body portion and the outlet end member, and (iv) the interconnection between the outlet end member and the fluid line all define regions that must be sealed. The patented structure is deemed to reliably seal these various interface regions.
In order to incorporate a fluid system device of this type in a secondary line and interconnect a main process line, it heretofore has been necessary to include a conventional tee fitting in the main process line. Typically, the straight flow path of the tee fitting is aligned with the main process line and a generally perpendicular access passage of the tee fitting is connected to the secondary line. A small length of fluid line is, therefore, positioned between the tee fitting and the fluid system device to interconnect the body with the main process line. Two connections between the main process line and the tee fitting result and an additional interconnection is required between the tee fitting and the secondary line. Essentially, a shortened length of secondary fluid line extends between the tee fitting and the fluid system device, thus increasing the space required to accommodate all of the various components. Since space is at a premium in many fluid environments, it has been deemed desirable to eliminate the shortened portion of secondary line between the fluid system device and tee fitting.
Additionally, it is always deemed desirable to limit the number of junctions in a fluid system. The time necessary to complete the connections and the components required to complete the connections can add considerable cost to the fluid system. Therefore, eliminating unnecessary junctions can result in significant economic benefits. The subject invention accomplishes all of these goals and overcomes the shortcomings of prior arrangements by decreasing the number of connections, providing ease of assembly, and reducing assembly and repair time.